Automatic can opener



Dec. 18 1951 A. H. JENSON AUTOMATIC CAN OPENER Filed May 3, 1948 5 Sheets-Sheet l 1360- 1951 A. H. JENSON AUTOMATIC CAN OPENER 5 Sheets-Sheet 2 Filed May 3, 1948 7 6 m 3 w a wk w w 7w 5 f- .M w

WZJZZwMEk WW A. H. JENSON AUTOMATIC CAN OPENER 3 Sheets-Sheet 5 Dec. 18, 1951 Filed May-3, 1948 I, I N V EN TOR. Q'rZ/zarfl Jewam Patented Dec. 18, 1951 UNITED STATES PATENT OFFICE AUTOMATIQ CAN OPENER Arthur H. Jenson, Evanston, Ill.

Application May 3, 1948, Serial No. 24,704

This invention pertains generally to an improved, automatic electric motor-driven opener for conventional types of, sealed metal cans and related containers; and more particularly to certain improved cutter and can driving components of such a device.

It is a general object of the invention to provide such an -'automatic, motor driven can opener adapted for household use or for use in commercial or industrial establishments, such as hotels, restaurants,institutions and other users of large quantities of canned commodities, edible or otherwise, which opener is characterized by a cutter and can driving unit adapted to be operatively engaged with and disengaged from a can to be operated on by a simple and quick operation of an improved control or actuating arrangement; which has a relatively inexpensive, electric motor actuated, rotary can drive, adapted to rotate the can relative to a cutter blade of said cutter-can drive unit with ample power and proper speedto produce a rapid severance of the can top, accompanied by the smooth ironing of the cut edge of the can inwardly along the inner margin of the can body; which incorporates provisions for automatically discontinuing operation of the-can driving motor in the event an undue frictional resistance or cutting load is encountered in the cutting operation; and which possesses various specific improvements as regards the manner of mounting its cutting blade relative to a can rotating roller, the shape of said blade and certain provisions for resiliently and removably associating the same with a fixed cutter head.

A further and more specific object is to provide a can opening device of the type described characterized by a unitary can drive and cutter assembly which is manually shiftable relative to a, can for penetrating engagement of its cutter with the latter and for driving engagement of a knurled rotary drive wheel with the can, in which said cutter includes a cutting blade of improved shape for its intended function, together with novel provisions for yieldably mounting said blade to improve its action in penetrating and severing the can cover.

A still further object is to provide such a cutter and can driving assembly which also incorporates improved means for guiding the usual peripheral bead of a can be opened into operative position relative to a rotary can drive wheel, in which position the can cover is penetrated by the aforesaid cutting blade; for resiliently mounting said blade in said assembly to improve the efiiciency of cover penetration and cutting by the blade;

7 Claims. (01. 30--4) and for partially or wholly withdrawing the can cover from the can after it has been cut by said blade.

Another specific object is to provide a cutter assembly for a can opener of the above type including a cutter supporting head mounted in fixed relation to a can driving element, enabling positioning of said head and element as a unit relative to a can, together with an improved, resiliently mounted cutter blade cartridge or unit which is removably mounted on the head for the purpose of facilitating cleaning or sterilizing of the blade whenever desired.

Yet another-object is to provide an improved cutting unit of the sort referred to, including a cutting blade whichis curved in outline relative to two intersecting planes, for improved cutting and ironing action with a minimum of friction loss, and an improved resilient mount for said blade.

Yet another object is to provide a cutting unit of the foregoing character having a permanent magnet associated therewith which is operative to remove the out can cover upon relative movement of said unit and can following the cutting operation.

A further specific object is to provide a can cutting blade of, improved, generally spherical section, curved re-relative to two intersecting planes disposed at right angles to one another which is further characterized by means adjacent the cutting edge of the blade .adapted to engage beneath a can cover partially severed thereby, whereby to assist in holding or lifting said cover from the can.

The foregoing statements are indicative in a general way of the nature of the invention, but other and more specific objects will be apparent to those skilled in the art upon a full understanding of the construction and operation of the device.

A single embodiment of the invention is pre sented herein for purpose of exemplifioation, but it will be appreciated that in practically all of its aspects the invention is susceptible of incorporation in other modified forms coming equally within the scope of the appended claims.

In the drawings,

Fig. 1 is a front perspective view of the can opener in accordance with the present invention, showing in dotted lines a conventional, hermetically sealed, cylindrical metal can positioned on the device preparatory to severance and removal of the can cover by said device;

Fig. 2 is a view in end elevation of the device,

partially broken away and in transverse vertical section, illustrating the can opener in the operative relation of the blade of its cutter unit relative to a can, and also indicating in dotted lines the functioning of the cutter unit in elevating the severed can cover after the cutting cycle;

Fig. 3 is a top plan view of the can opener, further illustrating certain operating details thereof, being partially broken away to show the driving provisions of the device;

Fig. 4 is a fragmentary schematic plan view on a somewhat enlarged scale, illustrating the functioning of the improved cutter and can driving assembly of the device in severing the covers of cans of different diameter;

Fig. 5 is a fragmentary view in vertical transverse section through the cutter and can drive assembly or unit of the present device, illustrating specific structural details of the same, and their operation;

Fig. 6 is a bottom plan view of the unit, viewed from section line 6-6 of Fig. 5, further illustrating the means for elevating and lowering the cutter-can drive assembly; and

Figs. 7 and 8 are views in section along lines generally corresponding, respectively, to lines I--! and 88 of Fig. 5, further illustrating certain structural details of the cutter head and blade assembly of the device.

This invention provides an automatic, motordriven can opener suitable for domestic or commercial use in the servicing of all sizes and shapes of metal cans, round, square, oblong, oval or tapered. Although it is intended primarily for use in severing the hermetically sealed, beaded can cover along a out line coinciding and partially or wholly coextensive with the internal circumference of the can, it may also be used as a piercer for certain types of soldered cans not designed to be wholly opened, in the formation of any number of drain or vent holes therein, spaced appropriately from one another. In either of these applications the present device presents a substantial advantage of convenience in use because of its provision for the quick and easy removal of the cutter and/or piercing element for washing or sterilization whenever desired. Likewise, said element is of new and improved shape and is resiliently mounted to the end of effecting a better, smoother, quicker and safer cutting operation than has been possible in prior devices of like type.

An improved, positive motor drive is provided for a knurled or toothed rotary can driving wheel, through a suitable reduction gearing which serves without excessive power requirement to provide correct torque and rotative speed for the opening operation, thereby avoiding spilling, overflow or splashing of the can contents, with resultant mess and loss of time in cleaning. This holds true regardless of the size of the can being serviced.

Moreover, an automatic throw-out safety switch feature which, to my knowledge, is unprecedented in apparatus of the type under consideration, serves to protect the driving motor in the event a frictional, cutting or other overload is encountered in the can opening operation. Other improved features of the apparatus providing for increased speed and ease of manipulation, low cost of production, versatility of use as regards the various sizes and types of can which may be serviced by the device, will appear from the description to follow.

Referring to Figs. 1-3 inclusive, of the drawings, wherein the device as a whole is shown, the

4 can opener is generally designated by the reference numeral I0. Viewed externally, it comprises a rugged, preferably cast or stamped base I I supported by suitable friction cushions or legs II. A generally rectangular, box-like, sheet metal motor housing I2 is mounted along the rear of this base. Housing I2 communicates internally with a hollow vertical guide housing I3 for a cutter and can driving assembly which is generally designated by the reference numeral I4 and which is hereinafter described in detail, said housing I3 being in effect a vertical extension of the motor housing.

For the purpose of elevating and lowering the assembly I4 relative to a finished can supporting surface I5 on base II, the Vertical housing I3 is provided with a pair of similar internal, rearwardly facing, toothed racks I 6. These racks are fixedly disposed on either side of a vertically elongated guide slot I! in the housing front wall. A plate-like anti-friction, anti-stuffing shoe I1 may be applied to the front of housing I3, adjacent basesupporting surface I5, to protect the finish of said housing against nicking by the lower head of a can operated on. .Said housing I3 has a further, vertically elongated guide slot I8 in its side walladapted to accommodate the outwardly extending head-operating shaft I9 to which the operating handle 20 is afiixed.

A metal can 0 of well known type is illustrated in dotted lines in Fig. 1 in its position preliminary to penetration and severance by the cutting instrumentality-of the device. The disk-like can cover is'hermetically sealed to its cylindrical wall in a well known way by means including the peripheral, rolled, edge bead B.

Details of certain operating motor, reduction gear drive and safety throw-out provisions of the device are best illustrated in Figs. 2 and 3. They consist of a small, fractional horse power motor 22 appropriately mounted in the housing I2, the output shaft 23 of said motor having a worm 24 thereon, which worm is loaded by a coil spring 25 to resist torque. Worm 24 meshes drivingly with a worm wheel 26 which is laterally accommodatedin an arcuate side extension I2 of the motor housing I2. This worm wheel is fixed on a vertical shaft '21 which is appropriately journaled internally of the housing provisions. Shaft 21 has a pinion 28 on its lower end which transmits torque at reduced speed through the successive meshing gears29, 29, all suitably mounted for rotation, as by a closed hanger 30 in base II. Gear 29' is secured to the lower end of an upright shaft3I of hexagonal or other non-circular cross section which functions to rotate the rotary can drive means of the cutter-drive assembly I 4, in a manner hereinafter described.

Referring to Fig. 3, the motor driven worm 24 is associated with a standard overload safety switch, generally designated 33, in such manner that a dangerous increase in the resistive torque in the cutting operation, accompanied by a substantial retardation or stoppage of the drive shaft 3|, results in axial shifting of the worm 24. This correspondingly shifts a control pin 33' of switch 33 to operate the latter and interrupt the electrical circuit for motor 22.

Details of such safety overload or cut-out switch arrangements are well known in the art, hence it is not deemed necessary to illustrate or further describe the same. In this aspect the invention is of a general character, residing in the adaptation of safety provisions of the above type to the requirements of an automatic can.

opening machine which'is'u'sually under the control of an unskilled operator and which, lacking such provisions, might suffer motor damage, under a, condition of overload. In any event. frequent fuse replacement is avoided. A well known type of manual snap toggle switch 3 controls the main motor circuit, the wiring of which has not been detailed since it will be ohvious to one skilled in the art, on the basis of foregoing description; The switch 33 includes a manually operated reset button 36 for resumin motor operation after the source of shaft stoppage or retardation has been ascertained and corrected. Automatic re-setting is not desirable.

Details of construction and operation of the cutter-can drive assembly or unit M are illustrated in Figs. 2 through 7. They include a blocklike, vertically slidable support, generally designated 31 (see Figs. 5, 6 and 7) which ismade up of two coacting parts 38, 39. The roughened, serrated or knurled can drive wheel at and the cutter head or mount 4| of said assembly l4, as well ascertain other associated parts, are mounted on this support and the support is guided for vertical movement in the hollow vertical housing l3. Support parts 38, 38 are clamped together by small studs 42 and are shaped at their meeting faceswhereby, in the operative position thereof, they provide a forwardly opening, generally circular recess 43 in the support to accommodate the can drive wheel it. The wheel 45! has end and radial bearing engagement in recess 43. The support 3"! is bored vertically at 44 to receive the non-circular drive shaft 3%, which shaft is supported appropriately for rotation bythe housing structure.

The upper support part 38 also has a transverse bore 45 in which the manual operating shaft i9 is received and journaled. This shaft is provided with pinions 47 adjacent opposite ends of the sliding support 31' which mesh respectively with the fixed racks It in the vertical guide housing I3. Accordingly, upon rotative manipulation of the handle 25, the cutter head 4! and sliding support 3? on which it is fixedly mounted are adjustably positioned vertically'in said upright housing to enable penetrating en-v gagement of the cutting blade of the unit l4 with the can and removal following the cutting operation. r

This rack and pinion type of operating device has certain advantages as regards convenience, compactness and simplicity which render it especially suitable for use in an opener of the present sort. However, it is to be understood that the employment of various equivalent power multiplying and applying expedients in substitution therefor is contemplated by the invention. More ovenit will be appreciated that it is the relative movement of the assembly Hi and base H which is significant in the penetration of the can, being not necessarily confined to movement of the said assembly toward and from a fixed base.

It should be noted especially, with reference to Figs. 1, 2, 5 and 6, that the lowermost component part 39 of the block-like sliding support 3? for the cutter-can drive unit it has a downwardly and inwardly tapered, forward cam nose 48, the upper edge of which terminates imme diately adjacent and beneath the periphery of the serrated drive roller 40. This cam is for the purpose of positively guiding the can head B into operative drive relation to said roller.

The fixed cutter head 4| of the cutter drive assembly I4 is preferably in the form of an 011"- wardlyprojecting, rigid bracketof inverted U- shape having inwardly turned retaining ways or flanges on its lowersides. This bracket is rigidly secured in any desired manner to the upper support part 38 and projects outwardly through the guide slot I! of vertical housing i3. It is'open at its outer end for the removable, sliding, frictional reception of a cartridge-like cutter unit 5| of rectangular section, thereby enabling said unit to be removed from the head 4| for cleaning when desired. Said cutter unit 5| comprises a cutting knife 52 of generally L-shaped outline, on which the blade proper, designated 53, is integrally formed todepend downwardly. This blade is of generally spherical section, as illustrated in Figs. 4, 5 and 6, especially in the portion thereof which is directly opposed to drive wheel 40, being convexly rounded in this zone with respect to central planesextending at right angles to one another through .its vertical and horizontal dimensions. I find that this spherical configuration of 'the blade 53 greatly improves the ease of can penetration and the efficiency of the cutting operation, enabling a very desirable ironing of the cut can'edge with a minimum of frictional loss.

The curvature about a horizontal axis provides a desired can-entering and wedging action, in conjunction with-the cam guide surface 48 of support 31, while the curvature about the vertical axis adapts the blade to the corresponding curvature of the can and provides optimum cutting and ironing of the severed edge. Sufficient clearance is present between the blade tip and drive roller 40 to pass the head of various sizes of can, see Fig. 4., without excessive frictional scraping of the inner side wall of the can. In efiect, a line cutting engagement is insured along a peripheral line which just about. coincides with the inner can surface. The blade 53 is appropriately hardened and is ground to adownwardly and rearwardly inclined forward cutting edge. An abrupt shoulder 54 is formed on the concave surface of said blade adjacent the penetrating tip thereof. This shoulder assists in supporting the severed can cover, in conjunction with further means to be described.

The heel of the L-shaped knife 52 is mounted in a block-like cushion 55 of rubber or other resilient cushioning material, as by cementing or vulcanizing, and this blade-cushion assembly is enclosed practically in its entirety by an integral, thin metal sheath 55 whose dimensions permit its sliding reception in the rigid cutter head 4|,

, guided and sustained by the inturned flanges 50 of the latter. The rubber, cushion fills the in-v terior of the supporting sheath. 56, thus'preventing the accumulationof food matter in the hollow interior of the latter. The sheath itself substantially encloses the cushion, with the result that a sanitary, relatively sterile knife unit well adapted to thoroughcleansing is provided. A depression 51 is formed in the outer end of sheath 56 for the snap reception of the correspondingly shaped detent 58 on the free end of r a swingable cutter retainer 59. The latter is apficiently from the'oute'r end wall of sheath" 56 to permit some translational outward shifting of said knife, from the solid line to the dotted line position, as the knife blade 53 travels downwardly relative to the'upper beadB of can C and penetrates its cover. The inherent resilience of cushion block 55 renders the knife 52 entirely self-adjusting. It permits the translational shifting, and automatic return to original position while maintaining a sufiiciently snug engagement of the outer surface of the blade against the inner periphery of said bead to iron down the out can edge during cutting. When the'drive wheel 49 is rotated to rotate the can relative to blade 53, the latter leaves no dangerous, ragged burrs at the cut edge and produces no slivers or scrapings to be dropped into the can or picked up off its lip. Yet the line cutting action made possible by the vertically curved shape of the blade requires a minimum of power to drive the can.

The cutter unit is externally enclosed by a box-like, swingable cover 62, which, like the cartridge retainer 59, is pivoted on the head 4! at 60. Cover 62 also serves .as asupport for a permanent magnet 63, which is appropriately gripped in a space internally of said cover be tween opposed walls or flanges B4 of the latter. Sufficient vertical space is left between the retainer and cover 59, 62 to enable magnet 63 to gravitationally engage the disk which is severed from the can by the device, and to elevate said disk above the can, as illustrated in dotted lines in Fig. 2, when the cutter-can drive assembly 14 is elevated following the cutting cycle.

In the interest of preventing magnetic losses, the cover 62 and retainer 59 are preferably fabricated of a non-magnetic material such as brass, and the internal wall 64 whereby the mag net 83 is gripped is located so as to afford'an air space between the same and the adjacent cutter unit 5i, to the same end.

The operation of the above device is undoubtedly clear from the foregoing description. A can C is initially positioned on the supporting surface I5 of base II, with its center line coplanar with the axis of drive wheel 4|]. Handle 26 is then manipulated clockwise, as Viewed in Fig. l, to thrust blade 53 into the can cover, the can guide surface 48 immediately adjacent and beneath the drive wheel 40 serving to positively guide the bead of the can into the driving bite between the toothed periphery of said roller and said blade.

Cans of widely different shapes and diameters may be handled with ease, as illustrated in Fig. 5, in which it will be observed that the spherical contour of blade 53 adapts it for snug cutting and ironing engagement with the inner edge of large and small sized cans, denoted C and C" respectively. The device is equally suited for operation on rectangular containers and other more unusual shapes. 7

Switch 35 is next actuated to initiate operation of motor 22 and the can is positively driven at a low speed, depending on the gearing of the device and motor speed, to rotate and cut the can. The motor is de-energized when the cutting operation is finished, and, as will be apparent to those skilled in the art, suitable automatic cut-out provisions to this end may be built into the device, if desired. Handle 20 is then rotated in counterclockwise direction to raise the cutter-drive assembly, whereupon the magnet 63 simultaneously elevates 'thecut-out cover disk to a position clear of the body of the can.

As illustrated in Figs. 2 and 5, the abrupt lateral shoulder 54 on knife blade 53 acts in a positive manner to supplement the action of magnet 63 in preventing the severed disk from dropping into the can.

I claim:

'1. In a device for cutting the cover of a container from the remainder thereof, a rotary drive wheel adapted to be positioned in driving relation to a container surface and a penetrating and cutting blade in opposed relation to the periphery of said wheel, said blade extending generally parallel to the axis of rotation of said wheel and being of generally spherically curved shape on its inner and outer surfaces in the portion thereof directly opposite said wheel periphery, said surfaces being concave and convex, respectively, said blade being provided on the concave surface thereof with a projecting abutment positioned to extend beneath the edge of said cover which is cut from" the remainder of the container.

2. In a container cutting device, a wheel adapted to be positively rotated in driving relation to a peripheral container surface, a cutter unit, a support for mounting said cutter unit in operative relation to said wheel, said cutter unit being removably mounted on said support, and a retainer releasably engageable with said cutter unit to prevent displacement thereof away from the wheel axis, said cutter unit including a blade generally paralleling said wheel axis, a resilient cushioning element in thrust receiving relation to said blade and sustained by said retainer, and means mounting said cushioning element and blade as a unit for ready removal and replacement on said support.

3. In a container cutting device, a wheel adapted to be positively rotated in driving relation to a peripheral container surface, a cutter unit, a support for mounting said cutter unit in operative relation to said wheel, said cutter unit being removably mounted on said support for sliding positioning thereon in a direction transverse of the axis of rotation of said wheel, and a retainer releasably engageable with said cutter unit to prevent sliding displacement thereof away from the wheel axis, said cutter unit including a blade generally paralleling said wheel axis, a resilient cushioning block in thrust receiving relation to said blade and sustained by said retainer, and means mounting said cushioning element and blade as a unit for ready removal and replacement on said support.

4. In a device of the type described, a sharpened, pointed blade of generally spherical shape on its inner and outer surfaces, said surfaces being concave and convex, respectively, and the inner surface being provided with a laterally projecting abutment adjacent the point thereof, which abutment faces away from said point.

5. In an opening device of the type described, a supporting head, a knife unit including a projecting blade, a resilient block-like cushion therefor yieldably sustaining said blade, a support on which said blade and cushion are carried in relatively fixed relation to one another, and means for removably mounting said support on said head for simultaneous removal of said blade and cushion as a unit, and a drive memlgierd adjacent and in opposed relation to said -6. In a container opening device of the type described, a supporting head provided with a longitudinal guide way, a knife unit slidably receivable on said way for removal from said head. a retainer pivoted on said head for swinging movement in a vertical plane and releasably en} gageable at the free-end thereof and in spaced relation to its pivot with said knife unit to support the same against endwise displacement on said head.

7. In a container opening device of the type described, a supporting head provided withfa longitudinal guide way, a knife unit slidably receivable on said way for removal from said head, a retainer pivoted on said head for swinging movement in a, vertical plane and releasably engageable at the free-end thereof with said knife unit to support the same against endwisedisplacement on said head, and a removable cover for said knife unit pivoted on said head for swinging movement in a plane parallel to the plane of swinging movement of said retainer, said cover being provided with a magnet adapted to sustain an element cut by said unit. ARTHUR H. JENSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,553,442 Habeil Sept. 15, 1925 1,718,125 Edlund June 18, 1929 10 1,768,980 Haines July 1, 1930 1,845,213 Ames Feb. 16, 1932 2,029,812 Dazey Feb. 4, 1936 2,230,376 Cullen Feb. 4, 1941 2,437,234 Webb Mar. 2, 1948 5 2,452,178 Brownlee Oct. 26. 1948 2,484,616 Dulaney Oct. 11, 1949 2,508,106 Edlund May 16, 1959 FOREIGN PATENTS 20 Number Country Date 682,622 Germany Oct. 19, 1939 

